This invention relates to improvements in steering column assemblies, especially but not exclusively to electric power assisted steering assemblies.
It is known to provide a steering column assembly in which a steering wheel is connected to one or more road wheels through a collapsible or telescopic steering column shaft. The shaft is designed to collapse away from a driver of the vehicle if a load is applied to the steering wheel in the event of an accident. The shaft may comprise a single part shaft which has a weakened central section that will concertina under an axial load. Alternatively it may comprise a two part telescopic shaft in which one part slides axially into the other under an axial load.
To locate the steering shaft relative to the vehicle it is typically supported within one or more bearings carried by a steering column shroud. The shroud is in turn fixed to a part of the vehicle chassis or bulkhead. In the case of a collapsible steering column at least a portion of the shroud must also be capable of collapsing as a load is applied.
In almost all vehicle produced today the column shroud is clamped to a fixed portion of the vehicle in a way that permits the steering shaft to be adjusted for rake and optionally for reach. A lever-which must be located within easy reach of the driver-allows a clamping mechanism to be locked and unlocked to for the position of the steering column shroud to be adjusted. This enables the driver of the vehicle to set the steering wheel at the most comfortable position.